Model Railroading > Locomotive lighting issue

I ran this by a good friend here on TO off-line, but I know he's swamped at work, so since I have a somewhat-free weekend, I thought I'd try a bigger audience.  Nothing personal Lee! ;-)

I just finished adding my first-ever ditch lights ("Big Al" Mayo's Monster LEDs with a Loksound #73400-series plugged into a factory Atlas board), but I'm experiencing a lighting issue I can't explain.  I have the green LED wires routed to the 750ohm 1/4 watt resistor that was included by Big Al, which in turn is wired to the purple decoder output.  The red LED wires are wired to the positive headlight port on the factory board, as is the headlight's positive lead.  The headlight's negative lead is wired to the negative headlight port on the factory board.  I have no rear-facing lights of any kind, since my prototype always ran with multiple unit consists during the month I model.  I don't yet have my LokProgrammer, so the only changes I've made have been to reset the decoder (programming track reset and CV8=8) and reprogram the address.  

• When I turn on the headlight, it works fine.  
• With the unit running forward, when I turn on the ditch lights (F6) with the headlight still on, the DLs don't illuminate.  However, if I turn off the headlight and leave F6 active, the ditch lights turn on
• When I reverse the unit, the front headlight goes off and the front ditch lights turn on, as if they're being confused for the rear headlight.  

Any idea what I'm doing wrong?  I'm told that my wiring must be fine if the ditch lights are working at all, and that it must be a programming issue.  That being the case, am I safe to reassemble the unit and come back to it for programming changes once I get my LokProgrammer?  I'd rather not have to open it up again if I don't have to, but I'd like to get it in service so I can operate a bit until my LP arrives.

Also, I added ditch lights to a second Atlas GP38 this morning - this one with a Loksound Select #73600-series 4 Aux decoder, and experienced the very same issue, with identical symptoms.  So whatever I'm doing wrong, at least I'm being consistent about it. :-)

Finally, I'd like to add flashing strobe-style beacons to several of my models, but since they're finished custom jobs, I'd rather not have to disassemble the shells, remove the handrails and cab, etc. in order to gain access to the cab roof from the inside.  Is it possible to drill in from outside the cab roof, through the cab false ceiling and floor, and then feed LED wires in from above, topped with an appropriate strobe beacon?  If so, can anyone recommend an appropriate LED and strobe fixture?

Thanks in advance for any help.

Joe Atkinson
Council Bluffs, IA
www.iaisrailfans.org/../Sub4WestEnd

Is this occurring when the loco is running under its own address, when set in a consist ot both? At least some ESU decoders have to be programmed a certain way in CV's 21 and 22 for some of the light functions to work properly when set in consist mode.



Edited 3 time(s). Last edit at 10/15/16 13:03 by tehachapifan.

tehachapifan Wrote:
> Is this occurring when the loco is running under
> its own address, when set in a consist ot both?
> ESU decoders have to be programmed a certain way
> in CV's 21 and 22 for some of the light functions
> to work properly when set in consist mode.

Both are under their own address.

Once I have enough conversions done to start reassembling consists, my plan is to assign each locomotive in a consist to the number of the west leader.  This is done to overcome a Lenz shortcoming that would otherwise prevent all locomotives in a consist from recognizing some functions like the independent brake, dynamics, etc.

Joe Atkinson
Council Bluffs, IA
www.iaisrailfans.org/../Sub4WestEnd

Do you have or have you accessed online the manual for this decoder? It is available online via the ESU website. There you can check your wiring against the included diagrams and find the involved CV's. It seems like what you describe can be remedied via CV adjustments, provided the wiring is correct.

A picture is worth a thousand words, but no where do you mention anything about hooking your ditch lights to the Common output. It sounds like you are going through the headlight to do so. The red lead of Al's LEDs is the common, and the green should go to the function lead, with the resistor. You probably know all that, I just don't think I understand your setup completely. I'll have to think through this one.

Edit: I re-read your post and am wondering if going through the headlight is an issue. The ditch lights only working in reverse may be a sign that the headlight lead is interfering with them in forward when it is on. Them coming on in both directions should be the case since your are wiring of a separate purple function lead. I still think changing your common wiring route will help

Sean McCaffery

Posted from Android



Edited 2 time(s). Last edit at 10/15/16 13:49 by bigmc83.

Tehachapifan, thanks for the suggestion.  I did confirm my wiring against the ESU diagrams, and technically it appears to be correct.  I think. :-)  See below.

bigmc83 Wrote:
> A picture is worth a thousand words, but no where do you mention anything about hooking your ditch
> lights to the Common output. It sounds like you are going through the headlight to do so.

That's correct Sean.  From what I understood, tying my red LED lead into the positive headlight post is essentially the same as going to the common, but I thought it'd be cleaner this way.  

>The red lead of Al's LEDs is the common, and the green should go to the function lead, with the resistor.
> You probably know all that, I just don't think I understand your setup completely.

Always good to have confirmation!  I'm a complete newbie at this stuff, so don't be afraid to dumb anything down for me. ;-D

> Edit: I re-read your post and am wondering if going through the headlight is an issue. The
> ditch lights only working in reverse may be a sign that the headlight lead is interfering with them
> in forward when it is on. Them coming on in both directions should be the case since your are
> wiring of a separate purple function lead. I still think changing your common wiring route will help.

Thank you!  I'll definitely give that a shot.  I don't have any rear-facing lights wired in my locomotives, so I may try using the rear headlight's positive port to attach for my common.  If it works the same as the front, then worst case, the DLs work as long as the non-existent rear headlight isn't turned on, which should be perfect for my needs.  Since this unit's front headlight is still tied into the factory board, I still want to leave the blue common wire intact between the decoder and plug, so tying into that for the red DL common wires doesn't appeal to me if I can avoid it.  

I'll try to make the change tonight and report back on my findings.

Joe Atkinson
Council Bluffs, IA
www.iaisrailfans.org/../Sub4WestEnd

Joe,
I think you've got the problem figured out. I did that on one of my units when I installed ditch lights. I think with 3 LED's and all 3 resistors, the resistors draw so much power that there isn't enough left to light your LED's. I would suggest tying the LED's back to the common pad on the decoder instead of splitting from the front headlight. If you don't have a common pad to solder to, or don't know where it is, on one of mine, I hooked the ditch light common leads to the rear light common. That solved the issue since the ditch lights are never on when in reverse while the rear light is lit. That's an alternate fix (unless you plan to run with ditch lights on while the rear light is on). [EDIT: Just saw you mentioned you don't have rear lights. In that case, your ditch lights should stay on no matter what.]
Hope this helps some! Love your modeling! Let us know if you figure it out.
   -Caleb



Edited 1 time(s). Last edit at 10/17/16 19:32 by Trainatic.

Quick update:  I moved the ditch light LED common wires to the rear headlight common port, and the ditch lights now work when the headlight is on.

Joe Atkinson
Council Bluffs, IA
www.iaisrailfans.org/../Sub4WestEnd